Conventionally, a technology called map matching, which uses positional information acquired by use of a GPS or the like and map information provided in advance to specify a moving route has been known as one of functions of a car navigation system or the like.
In addition, for example, a fee-charging system known as road pricing in which a collection fee determined depending on a distance travelled in a fee-charging area is charged in a case of entering the fee-charging area and thereafter going out of the fee-charging area, and a fee-charging system in which a collection fee determined depending on a distance travelled on a fee-charging road is charged or an across-the-board road usage fee is charged in a case of entering the fee-charging road and thereafter going out of the fee-charging road, have been known.
In such a road pricing, the map matching described above is used to estimate a position on a map, for example, and this estimated position crossing a border between the fee-charging area registered in advance and the outside of the fee-charging area causes determination of entering the fee-charging area and going out of the fee-charging area.
However, for example, in a case where the border of the fee-charging area is set at a part of a complex intersection as shown in FIG. 10, a problem as follows is brought about.
That is, since the map matching is performed at regular intervals, even if a vehicle actually has moved on a moving route illustrated in FIG. 10 by a broken line, in a case where a position previously detected is a point A in the figure and a position detected next time is a point B in the figure, the moving route recognized instantaneously is to be a route illustrated by a solid line in the figure. In this case, it may be probable that erroneous recognition is made that a border D of the fee-charging area is not crossed.
Even in the case where the erroneous moving route is specified in this way, the on-board device, which has a function to correct the moving route by tracing back to its past, may correct this moving route ex post facto to recognize that the border of the fee-charging area was crossed.
However, in recent years, it has been demanded that a driver is instantaneously notified of an event of starting the road pricing or fixing the collection fee. In order to respond to such a demand, the erroneous moving route owing to the map matching described above needs to be corrected earlier.
There has been disclosed the following technology in Patent Citation 1 as a technology for improving an accuracy of the map matching described above, for example.
One or more candidate links are extracted with respect to a mobile object positional information by means of map data with positional information defined in units of links and the mobile object positional information to take one link as being definite from the extracted one or more candidate links. In a case where the moving route formed of the decided links is discontinuous, candidate links for interpolating a discontinuous zone are searched for to decide one link to be employed from the searched candidate links and the discontinuous zone is interpolated by use of the decided link.
Patent Citation 1: Japanese Unexamined Patent Application, Publication No. 2011-76279